My favourite combo so far is a mix of MDMA and MDA at roughly a ratio of 2:1... Then follow it up with a dose of 2C-B at t+3-4 hours. For some reason 2C-B seems to be best taken on the MDMA comedown, wonderful synergy there. It can be even more fun if you add a bit of acid into the mix at the same time as the 2C-B. be prepared for a long night ;-)